• Excel spreadsheet for the FEL settings is here.
  • Common trajectory latest values for the X-ray mirrors are here.


Is there an issue? Escalation Path

  • Issue concerns X-ray beam delivery: see here
  • Issue concerns ECS: see here

Program

  • align the beamline with no CRL from source to Zyla, including the 45° yag at TCC
  • set and log all references in the preset file here
  • Timing
    • At TCC
      • Fine timing
        • close the iris to fully illuminate the imaging system for the spot size while the GAIA is timed out and the EL is OUT
        • move to the 45° Yag crystal extending from the pillar
        • send the optical laser then send the X-rays at full beam
        • timing should be within 20 ps, so changing the VITARA timing by 1 ns should allow us to see the image turn black. Closing the slits to 400 mic for the X-rays help see the localized change of indesx of reflaction
        • once you see a darkening, follow the procedure below to get timed
          • go back half the last step you just did (let's assume you are going negative on the vitara)
          • if you see no darkening, it means you passed t0 and you can go back positive again half the step size you did just before
          • if you see drkening, you didn't go far enough, so keep going negative until the darkening disappear
        • once the timing is done within 100 fs, close the slits to 50 mic and confirm spatial overlap with the pin at TCC
        • record positions of the VITARA for t0 and positions of the varioous targets to be able to go back quickly to this configuration and check timing
      • with the TSO imaging and the 45° YAG extending from the pillar,
    • At the time tool
      • Fine timing
        • Temporal calibration
          • make sure the Si 10 mic fothick foil is inserted (still) in the beamline
          • open the slits 2 to 0.4 mm
          • set a cross on the edges in the spatial direction, and save a run (spatial calib)
          • open the slits 2 to 0.1 mm
          • set a cross on the edges in the spatial direction, and save a run (spatial calib)
          • extract the mic/px value from this calibration (it is correct in both space and time axis since the objective looks at the yag/Si normal to its surface)
          • open the slits 2 to 2 mm
          • move the delay stage of the timetool by 149.8 mic (1ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
          • save a white field at that position
          • move the delay stage of the timetool by -149.8 mic (-1ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
          • save a white field at that position
          • move the delay stage of the timetool by 0 mic (0ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
          • save a white field at that position
    • Timing could check with the prefocusing lenses
  • MXI alignment at 9.5 keV
    • confirm the alignment of the pins at about 0 mm position on X of the MXI hexapod
    • start alignment with x2 on the Zyla objective

    • set full energy beam without prefocusing lenses in to start with

      op.SiT(1)
    • move +14mm relative to this position to get to the 25 x 50 mic stack for 9.5 keV
    • if you are lucky, you might see light through the MXI
      • if yes, start aligning the lenses with the 'fish eye' method: intentionally move V to create a symmetric pattern on the image and align tip, then intentionally move U to create a symmetric pattern on the image and align tilt
      • once both axis are symmetric, close the slits to 50 mic and translate X and Y to center the image on the original beam position when the MXI was out
      • keep iterating until the feature is round
    • record positions of the hexapods at this Z value in the preset to be able to come back when necessary
    • save this position on the first preset of the virtual motor
    • align the virtual motor by moving Z 10 cm away and realigning the MXI following the steps above
    • once done, save the position on the second preset of the virtual motor
    • confirm alignment by moving 10 cm away in Z using the virtual motor only
    • save 1000 images of the beam going through the MXI and no target at TCC
      • confirm the XRT spectrometer is in
    • insert a Siemens star at TCC

    • reduce intensity to 1%

      op.SiT(0.1)

      or 10% if you see nothing

    • confirm you image the siemens star pattern correctly
      • play with the focus of the MXI until the image is the sharpest
      • update the virtual motor
      • save runs of 1000 images (could be 10 x 100)
    • you might try to image other samples
      • try the targets produced at Stanford and experience alignment procedure
  • Plans for shots on target
    • Obtain Talbot with the Siemens star
    • Shots on target
      • start with e- spectrometer friendly targets to confirm we have a trace there (last pillar)
      • then move to regular pillars
    • perform Talbot at late delays
    • scan in MXI focusing at fixed timing and energy
    • scan in time at full energy
    • scan in intensity (energy) at fixed timing

Be CRL parameters

      • XRT sets
        • Set 1 (1500 mic)
          • @ 9.5 keV, FWHM at MXI lens is 500 mic
          • @ 11 keV, FWHM at MXI lens is 571 mic
        • Set 2 (2x1000 mic = 500 mic??) -not used
          • @ 9.5 keV, 62 m : too short focal length so not used
          • @ 11 keV, 88 m : too small beam so not use
        • Set 3 (1000 mic)
          • @ 9.5 keV, FWHM at MXI lens is 340 mic
          • @ 11 keV, FWHM at MXI lens is 460 mic
      • Hutch sets
        • Set 1 (2x100 + 1x200 mic) + 400mic pinhole
          • @ 17 keV, FWHM at MXI lens is 374 mic
        • Set 2 (6x300 mic) : 800 mic pinhole
          • @ 9.5 keV, FWHM at MXI lens is 286 mic
          • @ 11 keV, FWHM at MXI lens is 416 mic
        • Set 3 (5x300 mic) : 800 mic pinhole
          • @ 9.5 keV, FWHM at MXI lens is 371 mic
          • @ 11 keV, FWHM at MXI lens is 480 mic
      • MXI sets
        • Set 1 (50 x 50 mic)
          • @ 9.5 keV, f = 1.323e-01 m
            • magnification: 4.5/0.132 ~ 34
          • @ 11 keV, f = 1.774e-01 m
            • magnification: 4.5/0.177 ~ 25
        • Set 3 (25 x 50 mic)
          • @ 9.5 keV, f = 2.646e-01 m
            • magnification: 4.5/0.264 ~ 17
      • Viable combinations

Alignment procedure

  • Prepare the hutch for the shift (done 1h before the actual start time)
    • open the grafana dashboards located here (requires UNIX login/pwd) to access beam owner, energies and coatings
    • no gate valve in the trajectory
      • check in the vacuum windows that no gate valves from the NEH to the MEC hutch are IN (red)
      • it is ok that the DG2 STP 1 is IN
      • it is ok that the GL window is IN in MEC

    • open the rolling status and confirm that no devices upstream the hutch obstructs the beam

      op.rs()

    • insert yag3 to provide a photon terminator before TCC prior to send any beam in the hutch

      op.yag3.insert()
    • confirm that the chamber is loaded with targets and being pumped down to be ready at the start of the shift
    • search the hutch but leave SH6 IN (you are not the beam owner yet)
  • 15 min before the shift begins, call ACR at x2151 to check
    • look at current ACR beam operator on shift here
    • confirm photon energy
    • confirm pulse energy
    • confirm pulse duration
    • confirm beam mode
    • confirm multiplexing mode
    • ask for an e-loss scan
  • transition to beam ownership
    • ACR calls you to confirm they are tweaking the beam for you
    • confirm with ACR that MR1L0 and MR2L0 have the right coating following this page
      • if moving the mirror yourself, then open MR1L0 and MR2L0 HOMS GUI located in the mechome > LCLS tab > HOMS overview button
      • set the coatings to the appropriate material as a function fo the photon energy as per the page from above
  •  getting ready to accept the beam:
    • close DG2 STP 1
    • make sure the reference laser is out (check in the rolling status)
    • confirm the target chamber is pumped down
    • insert the Be window IN the beamline
    • search H6 if not already searched
    • remove SH6 OUT of the beamline
  • beamline alignment
    • ACR calls you to confirm beam is ready for alignment

    • force close the pulse picker to make sure it does not let the beam propagate to the hutch yet

      op.pp.close()
    • check MR1L3 mirror OUT (-6000) position (XCS mirror)
    • check the XPP slits (slit1) are open (20mm, 20 mm) in the rolling status
    • open the mirror settings located here
    • confirm bending values for MR1L0 and MR2L0 (advanced)

    • insert YAG0

      op.yag0.insert()
    • confirm FEL beam is on the cross for the OUT position (undeflected beam)
    • confirm the shape of the beam is round (advanced)
    • set the MR1L4 coating as per this page
    • insert MR1L4
    • confirm FEL beam is on the cross for the IN position (deflected beam)

    • insert YAG1

      op.yag1.insert()

    • remove YAG0

      op.yag0.remove()

    • remove all Si attenuators (send full energy beam)

      op.SiT(1)

    • open the pulse picker

      op.pp.open()
    • fine tune the pitch of MR1L4 to center the beam on YAG1

    • insert YAG3

      op.yag3.insert()
    • remove hutch Be CRL (Mechome > Beamline > Beamline CRL(hutch))

    • open slit 2

      op.slit2.move(5)

    • remove YAG1

      op.yag1.remove()
    • fine tune the pitch of MR1L4 to center the beam on YAG3
    • to adjust the height using the YAG3 red cross centered at (265, 282), call ACR, and for a 200 mic motion on the yag, ask them to move 200/4 mic up or down.
      • you could set SiT(0.2) to not saturate the image
      • you could set 10 images averaged to get a cleaner picture
    • log the mirror settings in our table here
    • confirm photon energy and lens stack to use and log the change of stack in the paper authorization document for Be CRL log

---------- not for SPL ---------

  • once they are done tuning
    • timing check
      • turn off laser triggers

      • go to the titanium foil:

        op.ti()
      • move hutch CRL out

      • set slit4 to 400 mic: 

        op.slit4.move(0.4)

      • send full beam on titanium: 

        op.SiT(1)

      • set the EVR to 10 Hz settings: 

        op.lpl_check_timing(rate='10Hz')
      • set vertical division to 10 mV/div on oscilloscope Lecroy 1
      • once you see the signal of the X-rays, set 100 sweep to average the signal
      • save it on memory 2
      • set back sweeps to 1 on channel 2
      • move target about 0.8-1 mm negative to target the Al frame
      • turn on the LPL trigger on, event code 43 for 10Hz
      • once you see the signal of the LPL, set 100 sweep to average the signal

      • move timing to overlap the LPL with the memory trace 2 using the python command

        op.nstiming.mvr(2e-9)

        to move the LPL 2 ns later than the FEL, but this is just an example! Move it (or not) by the necessary amount to overlap best the rising edges of the beams.

      • save the current value as our t0, using hte python command 

        op.nstiming.save_t0()
      • once timed, set 100 sweep to average the signal and save the trace on memory 3
      • take a screenshot and put it in the elog
      • move back the hutch Be CRL
      • set the slits back to data-taking move size

      • set the EVR to single shot settings: 

        op.lpl_check_timing(rate='single')
      • set the scope Lecroy 1 channel 2 voltage/div to the maximum (1V/div) to be able to observe the shot on the diode and monitor the timing